242 PROCEEDINGS OF THE ACADEMY OF [April, 



errors were due to the fact that in these portions of the range 

 of typical luridus, frequent females are met with which are larger 

 and decidedly heavier than specimens of the same sex from further 

 north. This must be attributed to variation in I. luridus, for the 

 southern race differs in all important respects from such material 

 quite as decidedly as it does from typical luridus. 



The great amount of variation in the present species is partially 

 shown by the following table of measurements of the extremes of 

 various series before us. 



Measurements (in millimeters). 



Caudal Length of 



Length width of Length of caudal 



cfcfi of body. pronotum. tegmen. femur. 



Aweme, Manitoba (2) 10 °1S-19. 1 2.5-2.8 16-16.4 10.8-11.1 



Pequaming, Michigan (1) 17 2.4 13.7 10 



Cape Cod, Massachusetts^) 17.4-18.3 2.5-2.6 12.4-13.1 10.2-10.5 



New Haven, Connecticut(S) 18.5-19.5 2.8-3.1 12.7-15.4 11.7-12 



Stafford's Forge, N. J (11)17-20 2.7-3 12.9-15 10.5-12 



Mount Pisgah, N. C (8) 18.5-18.8 2.7-2.8 13.8-14.6 10.7-11.6 



Pinnacle Peak, Ga (1) 19.2 3 14.9 12.3 



9 9 



Aweme, Manitoba (2) 20.2-21.7 3.2 16-16.3 11-11.7 



Pequaming, Mich (8) 19.6-20.3 3.1-3.4 15.9-17.8 10.8-11.6 



Cape Cod, Mass (2) 23.5-25 3.5-3.7 15.7-15.8 12.9-13.3 



New Haven, Conn (7) 23.7-27.4 3.5-4 15.2-17 13.2-15.3 



Stafford's Forge, N.J (8) 22.5-25.2 3.4-4 11-16 11.8-14 



Mount Pisgah, N. C (7) 22.4-24 3.4-4 13.4-16.9 12.5-13.2 



Pinnacle Peak, Ga (3) 24.8-25 3.4-3.8 16.7-18 14.3-15.3 



It would be difficult to imagine individuals, without even racial 

 significance, differing more greatly in general appearance than do 

 the long-winged slender examples from the northwestern portion of 

 this insect's range, from the heavy shorter-winged type which is often 

 found in Connecticut and New Jersey southward through the 

 Appalachians. This is particularly true of the female sex; north- 

 western material bearing a strong superficial resemblance to M. 

 atlanis, while the southeastern material is vastly heavier with a very 

 different general appearance. Intergradation between these types 

 is, however, almost everywhere to be found and no valid reason 

 exists for separating eastern and western material as geographic 

 races. 



Melanoplus luridus keeleri (Thomas). 



Virginia. North Carolina. 



Petersburg, VII, 23, 1913, (R. & H.), Weldon, VII, 24, 1913, (R. & H.), 



1 d\ 1 juv. cf . 2 juv. <?, 3 juv. 9 . 



ioo The figures in parentheses indicate the number of specimens measured 

 from each locality. 



